Hello, That is because of Flood Mitigation feature of Forefront TMG: http://technet.microsoft.com/en-us/library/dd441028.aspx Please add it as an exception or increase the limit. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner 2010 / 2011 Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows 7, Configuring Microsoft Certified Technology Specialist: Designing and Providing Volume Licensing Solutions to Large Organizations Microsoft Certified IT Professional: Enterprise Administrator Microsoft Certified IT Professional: Server Administrator Microsoft Certified Trainer

Hi everyone. I have a Windows Server 2008 running Forefront TMG (Version: 7.0.8108.200). Occasionally (about twice a day), all internet traffic stops working. Checked the event viewer on the server and the following message seems to be related the problem. "Forefront TMG disconnected a non-TCP connection from 192.23.45.67 because the connection limit for this IP address was exceeded. Larger custom connection limits should be configured for the IP addresses of chained proxy servers and back-to-back Forefront TMG computers with a NAT relationship." Changed for the purpose of this post (obviously), but 192.23.45.67 is the domain controller (running server 2003), and this TMG server is a different server entirely. Restarting the TMG firewall service resolves the problem, but not permanently. Is there a permanent fix for this? Never had the issue with the old ISA server, but this has been a regular occurrence with this new TMG server. Many thanks in advance for your help. Steve

Hello, That is because of Flood Mitigation feature of Forefront TMG: http://technet.microsoft.com/en-us/library/dd441028.aspx Please add it as an exception or increase the limit. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner 2010 / 2011 Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows 7, Configuring Microsoft Certified Technology Specialist: Designing and Providing Volume Licensing Solutions to Large Organizations Microsoft Certified IT Professional: Enterprise Administrator Microsoft Certified IT Professional: Server Administrator Microsoft Certified Trainer

Hey, thanks for that. I have applied this change so will see how we get on. I will report back either way. Thanks Steve

ask here http://social.technet.microsoft.com/Forums/en-US/Forefrontedgegeneral/threadshttp://www.arabitpro.com

Hi everyone. Just reporting back. I added an exception in the flood mitigation settings for our domain servers, but this has not made any difference. All external internet access (and Outlook Web Access) goes down at least twice a day. A restart of the Forefront TMG service gets things working again. I therefore just turned off flood mitigation altogether. But again, the same occurs. If a restart of the firewall service gets things working again, something else must be causing it to stop, but nothing in the event viewer to suggest what this might be. Is anyone able to offer any other possibilities I can try?Thanks Steve